Bass Traps

[apl]

Can i make this trap by gluing the fiberglass on gipsum boards or wood boards or must it be only fiberglass???

Do I fix it on the wall or must it be selfstanding and little away from the wall??

thanks guys.

No. You need to make a frame. The sound needs to be able to travel through the fiberglass into the corner and try to come back through it again. Putting wood right behind the fiberglass in the corner takes the space behind the corner out of the picture. Instead of wood consider hardware cloth or chicken wire.

 

[skaman]

Hi! And one Hi for the last post. Im very sorry couse i didnt wrote Hi. It wont happen again. I really must be a jack - ass!

Aha. I tought so, but I reather asked. Than i will do some frame, no problem.

Thanks guys!

 

[travelin travis]

It's not the air behind it that gives the benefit, it's the distance from the face of the insulation to the hard boundary. That distance gets you closer to the 1/4 wave length of deeper frequencies where the most efficient absorbtion occurs with velocity absorbers.

There are 4 thing that can impact how deep an absorber will be effective:

1. Thickness
2. Density (to a point)
3. Distance from the boundary
4. Gas flow characteristics

When doing a solid corner instead of straddling it (assuming the same material), the thicker one will do a better job down lower.

So greater distance from the wall equals better absorption?

 

[apl]

So greater distance from the wall equals better absorption?

Better in low frequencies. The rule of thumb is to use an airgap equal to the material thickness.

 

[bpape]

For getting reflection point absorbers and front walls (and other parallel to the wall mountings) to go deeper the gap=thickness works very well. A case of diminishing returns after that.

In a corner bass absorber application, I'd get as much as you can (within reason). I'd not limit myself to the above. A 4" slab only 4" from the corner won't work nearly as deep as 4" with the 17" gap. Not only is it a shorter distance, but it's also severely limiting the surface area of the absorber facing the room. The 17" is based on a 2' wide absorber.

 

[apl]

Yeah, the corner thing is different.